CAIRO — We had been detained by Egyptian authorities, handed over to the country’s dreaded Mukhabarat, the secret police, and interrogated. They left us all night in a cold room, on hard orange plastic stools, under fluorescent lights.

But our discomfort paled in comparison to the dull whacks and the screams of pain by Egyptian people that broke the stillness of the night. In one instance, between the cries of suffering, an officer said in Arabic, “You are talking to journalists? You are talking badly about your country?”

A voice, also in Arabic, answered: “You are committing a sin. You are committing a sin.”

We — Souad Mekhennet, Nicholas Kulish and a driver, who is not a journalist and was not involved in the demonstrations — were detained Thursday afternoon while driving into Cairo. We were stopped at a checkpoint and thus began a 24-hour journey through Egyptian detention, ending with — we were told by the soldiers who delivered us there — the secret police. When asked, they declined to identify themselves.

Captivity was terrible. We felt powerless — uncertain about where and how long we would be held. But the worst part had nothing to do with our treatment. It was seeing — and in particular hearing through the walls of this dreadful facility — the abuse of Egyptians at the hands of their own government.

For one day, we were trapped in the brutal maze where Egyptians are lost for months or even years. Our detainment threw into haunting relief the abuses of security services, the police, the secret police and the intelligence service, and explained why they were at the forefront of complaints made by the protesters.

Many journalists shared this experience, and many were kept in worse conditions — some suffering from injuries as well.

According to the Committee to Protect Journalists, over the period we were held there were 30 detentions of journalists, 26 assaults and 8 instances of equipment being seized. We saw a journalist with his head bandaged and others brought in with jackets thrown over their heads as they were led by armed men.

In the morning, we could hear the strained voice of a man with a French accent calling out in English: “Where am I? What is happening to me? Answer me. Answer me.”

This prompted us into action — pressing to be released with more urgency, and indeed fear, than before. A plainclothes officer who said his name was Marwan gestured to us. “Come to the door,” he said, “and look out.”

We saw more than 20 people, Westerners and Egyptians, blindfolded and handcuffed. The room had been empty when we arrived the evening before.

“We could be treating you a lot worse,” he said in a flat tone, the facts speaking for themselves. Marwan said Egyptians were being held in the thousands. During the night we heard them being beaten, screaming after every blow.

We were on our way back to Cairo after reporting about the demonstrations from Alexandria for The Times. We were traveling with journalists from the German public television station ZDF, a normal practice in such conditions — safety in numbers.

At the outskirts of Cairo, we were stopped at what looked like a civilian checkpoint.

We had been through many checkpoints without problems, but after the driver opened our trunk a tremendous uproar began. They saw a large black bag with an orange ZDF microphone poking out. In the tense environment, television crews had been attacked and accused of creating anti-Egyptian propaganda. We had been in the middle of a near-riot with the same crew the day before.

The crowd shouted and banged on the car, pulling the doors open. The ZDF crew in the other car managed to drive off, while we were stuck. Instead of dragging us out as we expected, two men pushed their way into the backseat. We were relieved that they were taking us from the crowd, until one pulled out his police identification. Rather than helping us escape, he was now detaining us.

The officer gave the driver directions to an impromptu police station in the Sharabiya district of Cairo, on the roof of a lumber warehouse. The officer in charge there, who identified himself as Ehab, said they were the secret police.

They searched the ZDF bags and found much more than just a camera. “We have a woman with a German passport of Arab origin and an American in a car with camera, satellite equipment and $10,000,” he said. “This is very suspicious. I think they need to be checked.”

Anxiety turned to anticipation when we were driven to a military base. The military had been the closest thing Egypt had to a guarantor of stability and we thought once we explained who we were and provided documentation we would be allowed to go to our hotel.

In a strange exchange that only made sense later, Ms. Mekhennet asked a soldier, “Where are you taking us?” The soldier answered: “My heart goes out to you. I’m sorry.”

After driving to several more bases we were told we were being handed over to the Mukhabarat at their headquarters in Nasr City.

It was sundown when they had us bring everything in from the car. The items were inventoried, from socks and a water bottle to a band of 50 $100 bills. Our cellphones, cameras and computers were confiscated.

We were taken to separate rooms with brown leather padded walls and interrogated individually. Mr. Kulish’s interrogator spoke perfect English and joked about the television show “Friends,” mentioning that he had lived in Florida and Texas.

The Mukhabarat has had a working relationship with American intelligence, including the C.I.A.’s so-called rendition program of prison transfers. During our questioning, a man nearby was being beaten — the sickening sound somewhere between a thud and a thwack. Between his screams someone yelled in Arabic, “You’re a traitor working with foreigners.”

Egyptian journalists had a freer hand than many in the region’s police states, but the secret police kept a close eye on both journalists and their sources. As the protests became more violent, a campaign of intimidation against journalists and the Egyptians speaking to them became apparent. We appeared to have stumbled into the middle of it.

We were blindfolded and led to the blank room where we would spend the night and into the next afternoon on the orange plastic chairs. The screams from the torture made it nearly impossible to think.

We were not physically abused. Ms. Mekhennet explained that she had been sick and a man appeared with a blood-pressure gauge, but she declined the offer. One officer gave each of us Pepsi and a small package of cookies. It was after 10 o’clock at night, and we had not eaten since breakfast, but the agonizing cries instantly stilled our appetites.

We were told we could go in the morning, and starting at 6 a.m. we asked repeatedly to be released.

Marwan first appeared around 11 a.m. He became visibly annoyed by our requests, complaining that thousands of Egyptians civilians were in detention. He did not appreciate our sense of entitlement.

That was when he opened the door and showed us our handcuffed, blindfolded colleagues from international news outlets. He said that he was exhausted, but would find our cellphones and computers.

About an hour later, we were given back our belongings. Our greatest fear, that the innocent driver would be kept for “processing,” did not come to pass.

We left together, with pangs of guilt as we saw our blindfolded, injured colleagues again, and new people led in, past guards with bulletproof vests and assault rifles.

Were we going to a hotel? we asked.

“You don’t get to know that,” a guard answered.

They put us in our car with orders to put our heads down. “Look down, and don’t talk. If you look up you will see something you don’t ever want to see.”

They left us that way for 10 minutes. The only sounds were of guns being loaded and checked and duct-tape ripping.

An interrogator appeared and asked our driver, “What did you do in Tahrir Square?” He said we weren’t there. The interrogator said to the driver, “So you’re a traitor to your country.”

In Arabic, Ms. Mekhennet, a German citizen with Arab roots, kept telling the questioner that we are journalists for The New York Times. “You came here to make this country look bad,” the interrogator said.

We were told we would be driving out in our car, but escorted by a man with an assault rifle. Again, we were told to look down.

Finally, after a while, our escort ordered the driver to stop the car and got out. “You can go now.”

The driver began yelling “Alhamdulillah” or “Praise be to God.” We looked around and realized we were alone, somewhere in the middle of Cairo, but away from the protests, the normal street traffic slowly moving past.

A version of this article appears in print on February 6, 2011, on page WK1 of the New York edition with the headline: Blood on the Nile: An encounter with Egypt’s secret police at the height of the crisis: ‘We could be
treating you a lot worse,’ said one.We knew. We had heard the screams. Order Reprints|Today's Paper|Subscribe